California declaring a public health emergency over bird flu, which hospitalized a British Columbia teenager for weeks. A fourth case of chronic wasting disease among deer. Tens of thousands of sea lions dying of H5N1.
Worries around zoonotic diseases — when infections spread between animals to humans or vice versa — have been in the news a fair bit recently.
The good news is that there are practical, everyday things we can all do to keep ourselves and our loved ones safe — and we can even keep enjoying being outside.
The Tyee sat down with Dr. Mayank Singal, public health physician for enteric, zoonotic and vector-borne diseases with the BC Centre for Disease Control, to ask him the best ways to navigate H5N1, chronic wasting disease, Lyme disease and rabies.
H5N1
Bird flu — the H5N1 influenza strain — is a virus that wild birds like ducks and geese occasionally get sick with. The Lower Mainland sits smack dab in the middle of the Pacific Flyway, a major migratory route that stretches from Alaska to Patagonia used by at least a billion birds every spring, and then again in the fall.
During migratory season, local cases of bird flu spike, usually when birds on poultry farms are infected after coming into contact with wild birds or their droppings. As of Dec. 14, 2024, the Canadian Food Inspection Agency reports it has culled more than 8.3 million birds infected with bird flu in B.C., which is millions more than in other provinces (the next highest rate is in Alberta, with two million birds culled).
The Canadian Food Inspection Agency says there is no risk of the virus transmitting to people who eat cooked poultry or eggs.
However, there is a risk of H5N1 jumping species, like when it jumped to sea mammals and killed 24,000 sea lions around the South American coastline in 2023.
H5N1 can be extremely dangerous when it jumps to humans. Earlier this fall a teenager in the Fraser Health region, whose identity was not released publicly, ended up in the intensive care unit at BC Children’s Hospital for weeks after contracting bird flu in B.C. It is still not known how the teenager got sick. The Tyee asked the Office of the Provincial Health Officer for a health update on the teenager in mid-December but a spokesperson said they hadn’t been given one.
Provincial health officer Dr. Bonnie Henry previously told The Tyee bird flu infections can have a 50 per cent mortality rate in kids. Adults tend to get a milder illness, though we don’t fully understand why. There have been around 900 confirmed cases of H5N1 in humans since it first appeared in Hong Kong in 1997, Henry added. Most of these cases have been in children in Southeast and South Asia, and most have been traced back to exposure to an infected animal.
The BC Centre for Disease Control’s Singal said they’re keeping a close eye on where and how the virus pops up, especially when it appears in mammals, because they’re one step closer to humans than birds.
Thankfully global cases of H5N1 infecting humans remain “relatively sporadic” and “we have not seen person-to-person transmission, which would be the most worrying,” he said.
The BCCDC has a handy resource on how to safely navigate being around potentially sick birds. The main advice is to avoid touching sick animals or their droppings, to not bring wild birds into your home and to keep pets leashed and away from animal feces.
Having a pet bird is safe as long as the bird is indoors and has no contact with wild animals or their droppings, Singal said. But if a pet bird gets sick, it’s recommended to keep the animal away from children and to contact a vet right away.
You can report sick or dead wild birds by calling the BC Wild Bird Mortality Line at 1-866-431-2473. If you have to handle a dead animal, it is recommended to wear a medical mask and eye protection, to maintain distance by using a tool or shovel, and to limit direct contact by using gloves, coveralls or a disposable gown, and disposable protective shoe covers.
Wash your hands with warm water and soap afterwards and throw your clothes in the laundry. Singal recommended using regular soap, not antibacterial soap, as antibacterial soap contributes to antibiotic resistance. Washing your clothes with hot water and regular detergent is enough to kill most pathogens, he added.
Finally, monitor your health for the next 10 days, and if you develop flu-like symptoms, contact a health-care provider and stay home. If you live with other people, wear a mask and wash your hands often until 24 hours after your symptoms clear.
Chronic wasting disease
Chronic wasting disease affects cervids like deer, elk, moose and caribou. It is caused not by a virus or bacteria but by an abnormally folded protein called a prion that affects the animal’s brain and nervous system. Symptoms may take months or years to show. The disease is always fatal. There is no treatment or vaccine.
The BCCDC says the disease causes small holes to appear in the brain, “so that it resembles a sponge.” This is similar to bovine spongiform encephalopathy, or mad cow disease, although chronic wasting disease doesn’t seem to infect cattle.
So far there have been four confirmed cases of deer infected with chronic wasting disease in B.C. The first case was reported in January 2024.
Considering that chronic wasting disease spreads through saliva, urine, other bodily fluids and carcasses, it’s “quite possible” we’ll see more cases, Singal said.
It’s not easy for a prion disease to jump species, but the “species barrier is not absolute,” he added. There is a possibility that the disease could jump to humans; therefore, it is recommended that humans avoid all contact with sick and dead cervids.
Prions are “very hardy” and still active even after an animal is dead, and they aren’t “deactivated” once cooked — so cooked meat is still dangerous, Singal said.
At later stages of the disease, animals will have symptoms such as weight loss, poor co-ordination, drooling, stumbling, trembling and lethargy, according to the BCCDC. But in early stages of the disease there may be no symptoms, so the only way to know is to test the animal.
In the Kootenays it is mandatory to have a sample (the head or a portion of the head) of any hunted mule deer, white-tailed deer, elk, moose or caribou tested before eating the animal. Trappers that collect roadkill are encouraged to avoid handling brain, spinal cord, eyes, tonsils, spleen and lymph nodes, because this is where prions can be concentrated, and to leave high-risk tissues at the kill site.
Transporting untested animals out of high-risk areas could contribute to the spread of the disease across the province, the BCCDC adds.
So what can you do if you come across a dead deer on or near the edge of the road? If possible, do not touch it and contact the Wildlife Health Office at 1-250-751-7246.
If you have to touch it, wear a medical mask and eye protection, maintain distance by using a tool or shovel, and limit direct contact by using gloves, coveralls or a disposable gown, and disposable protective shoe covers.
Wash your hands with warm water and regular soap and your clothes with hot water and detergent after.
Lyme disease
The bad news is that tick-borne diseases are expected to become more common as climate change makes Canada’s seasons balmier. The good news is that the most serious of those diseases, Lyme disease, is still quite rare in B.C., Singal said.
Ticks are small bugs that live in grass and forests and like to latch on to people, dogs and other animals that walk by. They can be found year-round but are most likely to bite in the spring, according to the BCCDC.
The BCCDC Communicable Disease Dashboard says B.C. rates for Lyme disease have stayed relatively stable over the last nine years, with the number of cases ranging from 10 to 41 in any given year. Last year there were 28 cases of Lyme disease in B.C., but only four of those were acquired locally. In a typical year, between one and 14 cases are acquired locally.
In Central and Eastern Canada, however, cases are rising sharply, with 144 cases overall reported in Canada in 2009 and more than 2,500 in 2023, according to the federal government.
The BCCDC recommends protecting yourself by wearing closed-toe shoes, long pants and long-sleeved shirts while walking in wooded or grassy areas. Wearing bug repellent with DEET or icaridin and tucking your pants into your socks and your shirt into your pants also helps keep them off.
After a hike, do a full-body check for ticks, taking extra time to check your scalp, folds of skin, under your arms and behind the knees. If you find a tick, remove it with tweezers and submit a picture of it to eTick for identification.
You can have a hot shower to remove any loose ticks from the body, and throwing your clothes in the dryer on hot for 10 minutes will kill any stray ticks.
It can take between 36 and 72 hours for a tick to transmit any pathogens it might be carrying, so the sooner you remove it, the better, Singal said.
If you are bitten and develop a rash or get sick, you should speak with a doctor because antibiotics can be prescribed to treat Lyme disease, especially if caught early, he added.
Rabies
Rabies is another frightening disease that comes with a good-news twist because it is incredibly rare in B.C. and found only in bat populations, and even then only in 0.5 per cent of bats. In other provinces and territories, rabies has been found in bats, raccoons, skunks and red and Arctic foxes.
“Here in B.C., we don’t have terrestrial rabies,” Singal said, adding he can’t remember a single recorded case of rabies in a pet dog or cat.
“Even cases in wild animals like coyotes or skunks we’ll see only once in a decade. But it’s different in other parts of Canada,” he added.
The BCCDC estimates there are around 10 million rabies exposures around the world each year, with the vast majority of patients receiving treatment. Tragically, around 55,000 people, mostly children, still die annually from the disease.
There is roughly one human rabies case every 13 years in B.C. where a person is exposed to an infected animal and does not seek prompt treatment. A 21-year-old died in 2019, a 52-year-old died in 2003 and a 22-year-old died in 1985, according to the Vancouver Sun.
Unfortunately, rabies is a very serious disease where “death is almost certain” if someone does not get medical treatment before the onset of symptoms, which typically start between three and eight weeks after exposure.
There is no treatment for rabies, so after a person has been potentially exposed, they will be given the rabies vaccine and rabies immune globulin.
If someone is not vaccinated in time, they will develop a fever, headache and difficulty swallowing, have excessive drooling, muscle spasms or weakness and exhibit strange behaviour, which could include fearfulness, aggression or lethargy, or in the case of animals, they may appear unusually tame.
Infected animals usually die within 10 days of getting sick.
If a person is bit or scratched by an animal that seems sick or behaves strangely — a bat out during the day, for example — that person should wash the wound with soap and warm water under moderate pressure for 15 minutes and seek emergency medical care right away.
“It is unnatural for bats to be coming in contact with humans, so if they do, they’re more likely to be sick,” Singal said.
The 21-year-old who died in 2019 had a bat fly into his hand during the day and did not notice the small puncture wound left by its bite.
Because rabies is so rare in cats and dogs in B.C., vaccinations are recommended but not required for pets, Singal said.
He added that he also wouldn’t worry about possible exposure to rabies if a dog in a park jumped up and scratched him or bit him.
But dog bites can expose you to other pathogens, so make sure your tetanus shot is up to date and check with a doctor to see if they recommend preventive antibiotics, he said. Adults should get a tetanus vaccine every 10 years, or right away if they get a dirty cut or wound and it has been five or more years since their last vaccine.
